The umbilical cord winds up around a baby's neck in about 25 percent of deliveries. (It's called a "nuchal cord.") Most of the time, it stays pretty loose and causes no harm. Your OB will simply use a finger to slip the cord over baby's head at birth, or will clamp and cut it if it's wrapped too snugly. Occasionally, though, this can be dangerous (if it gets wrapped or knotted so tightly that it cuts off baby's blood supply). A decrease in fetal activity (keep up your kick counts and call your OB if you notice them slowing down) or an abnormal heart rate during labor are signs of a troublesome nuchal cord. The same goes for other tangles or knots that sometimes form in the cord.
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